Particular embodiments generally relate to heating cables.
In cold environments, pipes may transport substances, such as oil, steam, and other process streams, etc. When steam or other process streams are transported through the pipes, the heat from the steam or process stream may help keep the pipes from freezing. However, if the system malfunctions, or if the flow of the process stream stops, and steam is not transported through the pipes, the steam condenses and the pipes may freeze. Accordingly, an electric heater may be used to keep the pipes warm to prevent freezing.
Different long-line heaters, generically called heat tracing products, may be used to keep the pipes warm. For example, all types of heaters are used. However, not all heaters may work well at high temperature. This is especially important when substances are transported at high temperatures in the pipes. Also, if the heater fails, then there is a large likelihood that the pipes may freeze and fail. This is a costly repair for a company and very undesirable.
There are several types of series connected heaters and several types of parallel connected. Heat tracing circuits, i.e., the length of pipe that is to be traced, are of varying length. Parallel heaters are desired because they can be cut to length and do not have to be engineered for the particular circuit, as do series heaters. Another difference in heat tracing products is that most of them have polymeric elements or insulation, and some have only inorganic elements and insulation, the latter can withstand very high temperatures for long times. So called self-regulating heat tracers are polymeric based and have parallel circuits, zone heaters have resistance wire heating elements but are generally polymeric insulated. Series heating cables can be either polymeric insulated or have only inorganic elements and insulation, such as MI Cable. However these latter types are not cut to length.
Some problems with zone heaters that use resistance wires for heating elements are that a certain length of resistance wire needs to be included in a zone. Zone lengths become very long because of the length of resistance wire that has to be used. The length between two bared areas may be a zone and a certain amount of resistance wire needs to be included in between a zone to provide the amount of heat desired. Because a large amount of resistance wire may need to be included in between zones, zone lengths that are several feet long are needed. If a resistance wire breaks or a node is bad with poor contacts between resistance wires and bus wires, then an entire zone or maybe two zones do not produce heat. This results in significantly long cold lengths in damaged zone heaters.